Hi Dale
Sounds like the sister truck is in reduced speed due to a lift height switch failure. Probably thinks the forks are raised and limiting the speed into creep mode.
The one thats not moving could be popping up that error but might not be moving due to foot pedal problem, as you state you have replaced the foot pedal switch. it might be you have 2 faults on this one related to throttle the other with height sensor.
Does this truck use the curtis controller?
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